Highly Sensitive NO2 Detection and DMP Sensing at Room Temperature using Flexible SWNT Thick Film Sensor

Abstract

Low cost; easy to fabricate and flexible single wall carbon nanotubes thick film resistor (SWNT-TFR) for detailed study of NO 2 detection is reported. SWNT-TFR was fabricated by vacuum filtration technique on flexible polycarbonate membrane. SWNT-TFR sensor shows selective response to NO 2 . The response increases from 1.47 per cent to 17.34 per cent by increasing the concentration of NO 2 from 0.2 ppm to 10 ppm. Different energy sources, thermal and UV were explored for achieving fast recovery of the SWNT-TFR sensor. The results showed that the gas sensor shows fast recovery in the presence of UV radiation. The calculated detection limit (DL) is less than 764 ppt for NO 2 . This work suggests the possibility to utilize SWNTs-TFR as extremely sensitive NO 2 sensor. We are also presenting sensing of Dimethyl methylphosphonate (DMMP), a simulant of chemical warfare agent sarin, using SWNT-TFR. The CNT based sensor gives repeatable response of ~2.7 per cent for 500 ppm of DMMP.

Intelligent wearable and portable security detection technologies integrated into protective equipment: A review

“…This distinctive structure provides an advantage in detection. Kumar et al 52 were the first to employ vacuum filtration to fabricate a thick SWCNTs resistance sensor on a flexible polycarbonate film. This sensor exhibited a selective response to NO 2 , and its response rate increased with increasing NO 2 concentration, 53 as shown in Figure 3.…”